A critical review of the effect of calcitic aggregate on air-lime mortar

In recent years, the importance of aggregate type on the properties of mortars has become increasingly recognised. In the context of restoration, it is particularly important to achieve the optimum properties that provide the best compatibility between the repair mortar and the existing masonry. With that in mind, the properties of the aggregate should be given priority when designing the repair mortar mix. A critical analysis of the current state of the art is presented, identifying the areas of research that have not yet been explored thoroughly. The role of calcitic aggregates in mortar is one such area, and the paper presented here examines the notion that calcitic aggregates cause an increase in the strength of lime mortar. The review establishes the limited amount of knowledge existing on the subject and seeks to determine methods that will enable validation of the claim.